


The Dark Knight of Krypton

by Takara_Phoenix



Category: Arrow (TV 2012), Arrowverse - Fandom, Batwoman (TV 2019), Supergirl (TV 2015), The Flash (TV 2014)
Genre: Alternate Universe - Medieval, F/F, Femslash, Fluff, King Clark, Knight Kate, Princess Kara, Queen Diana, Secret Identity
Language: English
Status: Completed
Published: 2020-07-29
Updated: 2020-07-29
Packaged: 2021-03-06 01:28:15
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,733
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/25595041
Author URL: https://archiveofourown.org/users/Takara_Phoenix/pseuds/Takara_Phoenix
Summary: After years, Princess Kara's personal guard Alex is promoted to become general. Alex takes Kara's safety very seriously and holds a tournament to determine the best suited successor. A mysterious knight in black armor enters under the alias 'Dark Knight'.
Relationships: Kara Danvers/Kate Kane
Comments: 9
Kudos: 41





	The Dark Knight of Krypton

Batwoman || Kanvers || Supergirl || The Dark Knight of Krypton || Supergirl || Kanvers || Batwoman

Title: The Dark Knight of Krypton – And the Princess of Krypton

Fandom: DC Comics / Arrowverse

Disclaimer: All rights concerning the show reserved to Greg Berlanti and Marc Guggenheim, all rights for the comics reserved to DC. This fanfiction on the other hand is entirely mine. No money is made with this, though reviews are more than welcomed.

Tags: f/f, fantasy AU, secret identity, fluff, m/f

Main Pairing: Kate/Kara

Side Pairings: Oliver/Felicity, Clark/Diana

DC Characters: Kara Danvers, Katherine 'Kate' Kane, Clark Kent, Diana Prince, Lara Kent, Alexandra 'Alex' Danvers, Nia Nal, Winn Schott Jr., J'onn J'onzz, James Olsen, Luke Fox, Mary Hamilton, Jacob Kane, Oliver Queen, Felicity Smoak, William Clayton, John Diggle, Barry Allen, Iris West, Wallace 'Wally' West, Joseph 'Joe' West

Summary: After years, Princess Kara's personal guard Alex is promoted to become general. Alex takes Kara's safety very seriously and holds a tournament to determine the best suited successor. A mysterious knight in black armor enters under the alias 'Dark Knight'.

**The Dark Knight of Krypton**

_And the Princess of Krypton_

The royal family of the house of El had ruled Krypton for many, many generations. The people seemed to love their rulers and the rulers loved their kingdom. Ten years ago, King Jor El, his brother Zor El and their wives had died during a devastating attack on the capital city. It had been nearly fully destroyed. The still relatively young Prince Clark stepped up.

Now, he was King Clark, ruling the realm with his wife Queen Diana. They had two children, Princess Lara and the newly born Prince Jonathan. And then there was Princess Kara, the cousin of the king. After their parents had died, the two had grown up very close and the king was very protective of her, the only other survivor of their royal family.

Kara had grown up close to many members of the royal court beyond her cousin's family. There was General J'onn, who was absolutely loyal to the royal family. He had been the one to train Kara's personal guard Alexandra Danvers. Alex, she was like a sister to Kara. And next to Kara's handmaid Nia and her servant Winn, Alex was one of her closest friends.

Ever since Kara's family had died, Alex had been her personal guard. She couldn't picture not having Alex at her side. However, Alex was one of the best fighters of their kingdom and she had the chance of a great promotion. Kara knew she meant the world to Alex, but she also knew that Alex loved the world outside, loved protecting people – more people than 'just' this one princess. So Kara had put her foot down and insisted. Alex had to take the promotion and Kara would find a new guard. Though that was easier said than done, really.

"Alex, I'll be fine with any guard", sighed Kara annoyed, rolling her eyes.

"You _may_ be. But only the best will be good enough for you", argued Alex pointedly. "I'm not gonna trust any random soldier with your safety, Kara."

Kara groaned and leaned her head back, prompting her maid to chide her. "I'm trying to do your hair, Kara. Please keep still. And stop rolling your eyes. You know Alex isn't the only one thinking so. King Clark and even Queen Diana agree. And so does General J'onn."

"But a tournament", groaned Kara frustrated.

"You are literally the only princess alive who would groan and complain about having strong knights battle for the privilege of guarding your life", pointed Winn out.

Winn was perched on the windowsill, watching the knights train outside. Kara's eyes wandered to the still pacing Alex. Part of Kara understood, really. Alex worried and Alex wanted to at least ensure the best of the best would train Kara. However, Kara hated being the center of attention like this and she also hated playing the proper princess. She had never been a proper princess. She loved to read, loved to investigate, loved to _help_. Often, if she could, she would sneak out of the palace and help people in a disguise – well, not much of a disguise, but the proper princess with the complicated braids, jewelry and expensive dresses was practically a different person in normal farm-girl clothes (thanks to Nia). That... was going to end now, she supposed.

She had only been able to do this thanks to Alex, because while Alex always had a watchful eye on her and protected her, she also knew what Kara was doing – and was _helping_ her. Some random guard chosen in some silly contest wasn't going to allow the princess to endanger herself like this.

"Look at it from this angle; King Oliver and Queen Felicity are going to come. And so is Prince Bartholomew", offered Nia with a small smile. "That's going to be nice, right?"

Wiggling her nose a little bit at that. Mh. Nia had a point there. Kara was good friends with Oliver, Felicity and Barry (who hated being called Bartholomew). Oliver used to be the prince of their neighboring kingdom until his father's too early passing, while Barry was the charge of King Joe. Their three kingdoms bordered on each other and had been close for a long time.

"Maybe _one_ upside to a tournament", conceded Kara after a moment.

/break\

"Oliver. It is so good to see you."

Clark offered a sunny smile, maybe even a bit brighter as he noticed the way the other king was puffing out his chest, before the two men hugged. Diana was busy greeting Queen Felicity and Princess Iris. It was nice to see each other again outside of war and negotiations.

"Lara has grown so big", noted Oliver surprised.

The young Kryptonian princess was grinning broadly, straightening her back a little more to show off that she was indeed just a little taller than Prince William was. Not that William seemed to mind it, he had grown up surrounded by strong, powerful women – the Canaries, the greatest force their kingdom had, were exclusively female. William seemed mostly just glad to have a royal here who was his own age so he wouldn't _have_ to stick close to his parents at all times.

"You have also grown so big, Felicity", noted Kara surprised, eyebrows raised.

Felicity huffed softly, resting her hand on her pregnant belly. "Well, yes. That's what happens."

Her other hand reached out for her husband, gently linking their fingers. The smile on Oliver's face was so soft and so proud, it melted Kara's heart a little bit. The next moment, Kara was swept into a tight hug by Barry, who whirled her around. He was _very_ enthusiastic and fun.

"It's so great to see you again!", exclaimed Barry delighted.

He had been King Joe's charge since he was a very little boy and though technically not by blood or title, he was as much the prince as Prince Wally, who... had apparently already run off. Those two, it had always been hard to keep up with. In Krypton, only Kara had ever managed.

"What are we hoping for?", asked Iris curiously. "Handsome knight to save the day?"

"Future husband material?", tagged Barry on with an eyebrow wiggle.

Kara offered her most polite smile and giggle at that. It was not... _proper_ for a lady to long for other ladies. A princess even less so. The fact that she didn't find men attractive or interesting in _that_ way was... a problem and a well-guarded secret of hers. The only one who knew was Alex, because Alex was the same. It had brought them even closer together, though Kara had only learned by accident – by walking in on Alex kissing the sister of a royal guard behind the stables.

"If we could maybe first unpack before all royals get caught up?", suggested Diggle.

Diggle was the personal guard of King Oliver, had been his protector for many years. His best friend, really. Much like James was for Clark. Speaking of, James smiled and approached.

"I'll show you where you can stay. Tonight, there will be a feast for everyone", stated James. "I heard Clark talk to the head chef and... it's going to be a lot."

"I am looking forward to that", laughed Diggle. "It's been a while since I last had Kryptonian food."

"I'd like to just rest", admitted Felicity with a sigh. "All the up and down of the carriage..."

"She threw up six times on the way here", offered Oliver, getting elbowed by his wife. "Ouch."

Diana rolled her eyes and shook her head before offering Felicity her arm. "Come, I think it'd be wise for you to see our healer, just to make sure you and the little one are fine after the ride."

"The tournament will start tomorrow", declared J'onn as the group headed inside.

"And, as the head of the guard, will you host the tournament?", asked Diggle curiously.

"We... have had... other issues that I am currently concerned with. General Kane will oversee the tournament and he has also put it together", offered J'onn with a serious frown.

The house of El fell silent at that. Recently, it had come to their attention that during the attack on the castle that had killed the royal family and destroyed the castle and a majority of the city, some very dangerous criminals had escaped from the dungeon. They had been hiding away in a dark and dangerous territory of Krypton known as the Phantom Zone. J'onn was in charge of the investigations and... it was also the reason for Alex' promotion. J'onn wanted her on his team.

"General Kane? The head of the Crows?", asked King Joe with a deep frown. "I'm sure the tournament is going to be quite impressive then."

The Crows' reputation proceeded them. The royal guard of Krypton, counter part to the Canaries. It had King Joe joke quite often that he ought to name his own royal guard after some type of bird too.

/break\

Clark, Diana, Joe, Oliver and Felicity sat high on the first row, all royal and regal. Kara, Iris, Barry, Wally, William and Lara sat just one row below in the royal stands. William and Lara were whispering and giggling with each other, while Kara got caught up with the others.

"I heard you were very against this tournament", pointed Wally out.

"I mean, this is embarrassing", offered Kara with a small sigh. "A tournament to find someone to protect me like I'm some... helpless damsel in distress."

"I feel you on that", agreed Iris with a frown. "I'm glad I have Eddie. I know I can trust him, I... uh... trust him a lot. Having a contest to appoint a stranger..."

Kara made a small sound of agreement, but then the tournament finally started and her attention was drawn to it. Even if she didn't want the contest, she had to admit that it was good entertainment to have knights go at each other like that. Barry and Kara kept whispering with each other throughout the tournament and if nothing else, then Kara at least enjoyed having her friends over.

"Who is _that_?", asked Wally surprised, leaning forward.

"Definitely the most badass looking knight", declared William a little excited.

"Language", called Oliver out from the row above them, looking amused.

"He's right though, honey", commented Felicity. "That armor alone is amazing."

And it was. In came a Dark Knight – or so the announcer said. An anonymous stranger who had signed up under this very fitting alias. His armor was pitch-black but with some red symbol on his chest. Even Kara found herself interested at that, because something about the knight was different – even beyond the color-scheme. He wasn't as tall as most of the knights and not as broad either. But he was _strong_. He knocked every one of his opponents down from their horses and evaded their attacks brilliantly. Kara had to admit that it was impressive.

"That was a fascinating first day", commented Diana, looking pleased. "There are many worthy contestants and I can't wait to see who will win tomorrow's grand finale."

"Yes. And for now, I'm sure we have a good meal waiting for everyone."

Clark smiled and motioned for the other royals to follow him back to the palace, knowing that these kind of festivities always left one hungry. Kara however, she was less hungry and more curious. She wanted to know who was beneath the black helmet. Sneaking away was impossible with all the other royals with her, so she found herself forced to go along to the feast instead of investigate.

/break\

"How did I look out there, Luke?"

"Badass. I mean, you really showed them. You were easily the best one out there."

Kate smirked as she took off her helmet and ran her fingers through her short, sweaty hair. It got hot under those armors, even this special one that her friend Luke the smith's apprentice had forged for her. Special metal, less penetrable than the usual. And very stylish in all black. Luke, he was the only one who knew that Kate was the Dark Knight. It wasn't even the fact that she was a woman – considering the all-female Canaries of their neighbors, of the all-female Amazons of Queen Diana's home country, female warriors were not a rarity in their corner of the continent. The problem was Kate's... Kateness, one may say. Kate was born the daughter of General Kane, leader of the Crows. And all her life, she had worked hard to become a Crow but when the Crows' old-fashioned prejudices would not allow for a woman loving women. And Kate very unashamedly loved women. Her father may not hold it against her, but he was just a cog in the military wheel too and this was too ingrained into their society. She dropped out of training.

That didn't mean she lost her ambition though. She still wanted to be a knight, wanted to fight and protect. This right now may just be her only chance to become a knight. There was no limitation to the tournament. Everyone could join in and the one who would win would effectively become a member of the royal guard. Admittedly, a glorified babysitter for the princess, but still. It could be her stepping stone into a career as a knight after all.

"You should hurry up", noted Luke. "Your family is certainly already waiting for you. Another royal banquet for the guests and Lord Kane and his daughters are expected to show up."

Kate grumbled to herself as she got out of her armor, with Luke's help. The problem of a double life was being torn apart between the two lives. Her father knew she fooled around with women so whenever she ran late or skipped on something, he would just assume she had found some... bar-wench and got caught up in her skirt or something. That kind of reputation was helpful for a double life. It was still stressful though and it also led to people doubting her capabilities and character.

"You know", grunted Luke. "It is somehow easier helping you into the armor than the dress."

Kate chuckled softly as she straightened her gown. One of the problems about being a high-born lady was that she was forced to do certain appearances. Tonight, the king and queen were throwing a fest for all the royals and high-borns. Kate was not looking forward to this celebration though.

"Have fun and sneak me something out", called Luke after her as Kate ran out.

Kate took a couple of shortcuts to make it as quickly as she could and yet still she didn't escape her father's displeased frown. Well, at least her younger sister Mary seemed happy to see her. The two of them hugged before following their father toward the banquet hall.

"You missed quite the show, Kate", whispered Mary excitedly.

"I have a hard time believing that", offered Kate with a bored shrug.

Again with a judgmental look from dad before they found their places. They sat relatively close to the royal family and Kate couldn't help but sneak glances over at the princess every now and again. She had to admit that Princes Kara was pretty. Very pretty. And cute. The way she'd laugh and smile as she talked to the other royals and to her for now still personal guard Alex.

Kate wondered what being the princess' personal guard would entail, how it would actually be. Kara didn't strike her as the pompous pampered kind of princess. Still, babysitting was not exactly Kate's ideal gig, even if the princess in question was pretty to look at.

/break\

The tournament's second day was about to start and Kara was mostly tuning out how Winn, Nia, Iris, Barry and Wally did their speculations. About what high-born man may be behind that Dark Knight armor. They were also planning Kara's engagement, basically. Which, she understood where they were coming from. She was a princess of a certain age, it wasn't unusual to start looking for a good match-up. Iris was engaged to Eddie, a high-born royal guard who had been very loyal to King Joe for many years, even Wally was engaged to Jessie, a princess from a distant realm. Part of Kara always feared that she and Barry would be matched up one day. It would certainly not be the worst to settle with a good friend than a total stranger.

"Oh wow. Okay, that Dark Knight is _really_ impressive", grunted Winn surprised, backing off.

Considering all of this was about Princess Kara, she had insisted on giving her friends Winn and Nia also good seats with them. Both seemed to be enjoying the show. Kara was too, admittedly. The Dark Knight was truly impressive. He kept winning every single duel, be that on horseback or with a sword. Throughout the tournament, the Dark Knight prevailed.

"It seems we have a very clear victor!", announced Clark at the end of the day.

He stood, bright smile in place, arms spread. Him and Diana stepped up, as the regal royal couple they were. Completely in sync. Kara had always admired that about them. Not just their actions, but their decisions too. They ruled wisely, side by side. Looking between those two and Oliver and Felicity, Kara always found herself longing for this kind of love too. It wasn't realistic, of course. Being who she was, loving who she loved, there would never be more than secret meetings behind stables and stolen moments no one could know about.

"We congratulate you, Dark Knight", continued Diana as the royal couple approached the knight. "But now it seems time to reveal who is behind the armor, sir."

Kara shifted a little as she followed them, her focus on the Dark Knight. And then the helmet was removed and all Kara could do was stare. Her eyes were wide as a beautiful face was revealed. Short, messy dark hair, dark eyes, sharp features. She was _beautiful_. And a _she_.

"Kate!" Jacob Kane's voice thundered through the tournament grounds in rage.

Oh. Oh, that was why the beautiful face seemed familiar. Lady Katherine Kane. Kara remembered her, remembered them both. The Kane twins, Katherine and Elizabeth. Kara used to play with the two of them, with them and with J'onn's daughters. Elizabeth as well as J'onn's family had not survived the attack on Krypton's capital city, just like Kara's parents. Ever since, Kara had kind of lost touch with Kate. Supposedly, Kate had lived with her cousin Bruce while General Kane had investigated the attack together with J'onn.

"The rules are the rules, dad", stated Kate with a cocky little grin. "The victor becomes a knight."

Jacob Kane scowled at his daughter, though he had nothing to say to that, because Kate was right. Those were the rules. Everyone was free to sign up and the winner would become part of the royal guard. The winner would become Kara's personal protector. Kara's eyes widened as that realization fully settled in. Huh. Kate Kane was going to be her new personal guard.

/break\

"So—o, what do you think about your new guard?"

There was a playful smile on Felicity's lips as she stepped up to Kara. The two were outside, overseeing the yard where Lara and William were laughing and playing with Wally. The visiting royals wouldn't stay much longer, tomorrow morning they would be leaving again.

"I remember Kate from when we were little. I... guess it could be worse?", offered Kara.

Felicity hummed softly at that, folding her hands. "When Ollie was assigned John as his personal guard, he was _not_ thrilled either. Oliver hated the idea of having a stranger hover around and protect him like he needed protection. But this... stranger, he became Oliver's best friend. They're like brothers now, inseparable. I hope that you and Kate will grow close too."

Kara's eyes wandered over to Oliver and John Diggle, who were approaching the playing children. Oliver laughed brightly as William ran up to him, catching his son to whirl him around. Just as he put the boy down, Diggle ruffled William's hair. Yes, John Diggle wasn't just a royal guard, he was _family_. Alex was like a sister to Kara, James was like a brother to Clark.

"I'll miss Alex", whispered Kara softly. "I know she'll not be gone for good, but her investigations will take her... somewhere I can't go with her. I just... I don't... like change..."

"Change can be good too. Don't see it as Alex leaving, see it as... Kate arriving", offered Felicity. "You're not losing Kate, you're gaining someone new in your life."

The question was how that was going to play out. What role would Kate play in Kara's life...?

/break\

Kara stirred late at night when she heard strange sounds from the room next door. Alex' old bedroom. Kate's new bedroom. The room directly connected to Kara's chambers, so the guard could immediately come to the princess' aid if need be. Now, Kara used that door to see what strange sounds were coming from Kate's room. As soon as she opened the door, her eyes widened. A figure was climbing in through the window, the cloak billowing behind them.

"The Bat", gasped Kara wide-eyed.

And when the light of Kara's candle illuminated the figure, the princess gasped again. That was Kate. Kate was the Bat. Kara yelped and stumbled back some while Kate fully climbed into the room. There was a scowl on Kate's face at that, before she took off her cloak.

"Yes. I am the Bat, princess", grunted Kate.

The Bat was – well, Kara thought it was an urban legend, really. For many years, someone dressed in a black cloak that gave the illusion of looking like bat-wings had been going through town at night, helping the helpless. Kara never had a run-in with her though, despite her own night-time (and day-time) vigilantism over the past few years.

"You're the Bat", whispered Kara once more, blinking slowly. "Wow."

"Princess, you _can't_ tell anyone", grunted Kate seriously, stepping up to Kara. "I just... I need to help people. That is what I do. But if my father – if the royal guard – learn, I'm in trouble. We're supposed to uphold the law in our armor, not like this. But the royal guard fails and I pick up where it fails. I want to protect this city, this kingdom. That's why I joined the tournament. I want to do it right, but I also know I have to do it... like this."

Kara felt a weight being lifted from her chest. "I'm Supergirl."

The silence stretched on as Kate stared at her. " _You_ are... How?"

"Well, Alex knew. She helped me sneak out. She helped me... do the things I do. Did. It's part of why I didn't want a new guard, because with hawk eyes on me, how could I sneak out? But..."

"But if your guard is also a vigilante, you think you can continue?", grunted Kate.

"I mean... I've seen your work. Very impressive", offered Kara with a cheeky little grin. "We could work together? Give each other alibis."

Kate huffed, sounding half amused. "We could... see how it goes."

/break\

To say 'it went well' would be an understatement. Kara and Kate were the perfect team. They worked together so well and it was exhilarating for Kara to work together with another vigilante like this. They would sneak out together and climb back in together, collapsing on the ground, laughing from all the adrenaline and excitement. Just like today. Both laid on the ground, giggling to themselves. It happened nearly naturally. Kara rolled over, so did Kate. They looked at each other, laughter in their eyes as they leaned in slowly. And then they kissed.

"Kate, I-", started Kara, eyes wide and cheeks red as they parted.

"No. It's okay, princess", whispered Kate with a small smirk.

Her hand slipped around Kara's neck and she pulled the princess in for another kiss. Kara wasn't a pompous princess, not at all. She was... cute and soft and strong and proud and _kind_. It seemed impossible for Kate not to fall in love with Kara, especially when the two had started going out into the night together, relying on each other, fighting side by side.

"You're wonderful, Kara", whispered Kate softly. "You're... amazing."

"I... I... so are you", replied Kara, licking her lips. "I like you a lot."

That made Kate laugh a little before she pulled Kara close once more. Not for a kiss this time. She just wrapped her arms around Kara's waist to pull her against herself. Slowly, Kara settled down against Kate, resting her head on Kate's shoulder. The both of them slowly calmed down from the adrenaline of the night, leaving them drained. Even climbing up onto the bed seemed like too much work, so the two of them fell asleep arm in arm on the ground.

/break\

An upside of having Kate as her partner – the vigilante kind – was Luke, the smith's apprentice. He was really helpful for them. So was Kate's sister Mary, who soon enough had figured out the truth about Kate's night-time activities and who was the apprentice of the local physician. Because there were injuries from their vigilantism that were hard to explain to the royal physical for Kara.

Life was good. Kara had her new backup, she had her _girlfriend_ at her side. At all times. When they went out to protect Krypton at night, when Kara had to attend anything official she would have her royal guard at her side. It was easy to sneak kisses and gentle caresses in whenever they liked, because it was natural for them to spend a lot of time together.

Even though Kara still had to _hide_ it, she was happier than ever before. And there was even more. Kate was deeply interested in the happenings around the escaped prisoners hiding in the Phantom Zone, so she and Kara got more involved in Alex' investigations, trying to help – if not as a guard and princess, at least as Supergirl and the Bat. They were a brilliant team.

"I... I love you", whispered Kara softly, her arms around Kate's neck.

The two of them were in Kara's bedroom, standing together. Kate had her arms around Kara's waist, holding her close. There was kissing, every now and again, between words. Kara smiled gently, kissing along Kate's jawline. She had never felt this supported and understood in her life.

"I love you too, princess", grinned Kate, caressing Kara's side.

They had been out all night, taken down a gang – a ground of criminals who were breaking into shops at night. It had been so exciting. It was so good to have someone to rely on, to trust blindly to have their backs out there. To have each other. Kara grinned softly and took her tiara to place it on Kate's head and even though Kate scowled, it looked adorable. The princess and her gorgeous Dark Knight. Yes, life in Krypton and in the royal palace was good.

_~*~ The End ~*~_

**Author's Note:**

> THIS WAS FUN! Medieval AU is just such a nice shiny thing for the Dark Knight. And princess Kara is such a good aesthetic! ^o^
> 
> I had this idea over on tumblr originally (come visit me at [takaraphoenix](https://takaraphoenix.tumblr.com/)), when asked about various AUs for Kanvers and I really had to write this one!


End file.
